JP2004302010A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus whose actuation time does not become long even when a memory which requires a long time for reading is used to store variation data and control parameters. <P>SOLUTION: The image forming apparatus which stores the control parameters for controlling constitution components in a nonvolatile memory and is actuated by executing a series of actuation steps one after another, reads control parameters needed for next and succeeding steps out of the nonvolatile memory (S13, S15, and S18) during the execution of specified actuation steps (S12 to S14, S14 to S16, and S17 to S19). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image forming apparatus including a nonvolatile memory that stores control parameters and fluctuation data.
[0002]
[Prior art]
An image forming apparatus using an electrophotographic method includes a black-and-white or color copying machine, a printer, a facsimile, and a multifunction machine in which a plurality of these functions are combined. In recent years, most of such image forming apparatuses are of a digital type, and various functions can be used.
[0003]
Therefore, the amount of fixed data such as control parameters relating to basic control and various functions of the apparatus, and the amount of variable data such as a copy counter and various histories are increasing. A non-volatile memory is required to store such data due to the nature of the data, and the capacity of a rewritable non-volatile memory to be used has been greatly increased with an increase in the amount of data to be stored.
[0004]
In such a situation, it is conceivable to use an EEPROM (Electrically Erasable Programmable ROM) as a typical rewritable nonvolatile memory. However, as described in Patent Document 1, the EEPROM requires a long time for writing. There is a problem. In addition, since data for writing and reading are transferred serially, reading requires a long time. In particular, when the apparatus is started, it is essential to read the control parameters from the non-volatile memory. For example, when the control parameters of about 64 Kbytes are stored in the EEPROM, the reading may take several tens of seconds or one minute or more. Patent Document 1 proposes a method in which an EEPROM is used to store variable data such as the number of copies, and the variable data is not frequently written.
[0005]
It is conceivable to use a flash memory which is faster in reading and writing because data is transferred by a parallel bus as compared with the EEPROM. Is an obstacle to cost reduction. According to Patent Literature 2, a flash memory is used for storing control parameters and fluctuation data, and at the same time, the data is compressed and stored, and when necessary, read from the flash memory and decompressed and restored on an SRAM. I have. In this way, even if a flash memory is used, its capacity can be reduced to some extent, which can contribute to a reduction in the cost of the apparatus.
[0006]
[Patent Document 1]
Japanese Patent Application Laid-Open No. Hei 5-249969 [Patent Document 2]
JP-A-8-102812
[Problems to be solved by the invention]
However, the method proposed in Patent Literature 1 is a technique in which the fluctuation data is not written in the EEPROM every time the data is updated. Although the EEPROM is used as a memory for storing data, all the control parameters are written in the EEPROM. There is no proposal as to how to read data from an EEPROM having a low reading speed so as not to affect the start-up time when the device is started.
[0008]
Further, the method proposed in Patent Document 2 judges that it is inappropriate to use an EEPROM as a nonvolatile memory for storing variable data and control parameters, and compresses the stored data on a flash memory to reduce the memory capacity. It is intended to reduce costs by suppressing them. However, lossless compression of data usually has a compression ratio of about 1/2, and the cost can be reduced only to that extent. The use of an EEPROM can further reduce the cost of the device.
[0009]
The present invention has been made in response to such a problem, and provides an image forming apparatus in which the startup time of the apparatus does not become longer even when a memory that takes a long time to read is used to store variable data and control parameters. It is intended for that purpose.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, a control parameter for controlling a component is stored in a non-volatile memory, and a series of a plurality of startup steps are executed, respectively, in an image forming apparatus that starts up the apparatus. During execution of a predetermined start-up step, control parameters necessary for the next and subsequent steps are read from the nonvolatile memory.
[0011]
The above-described components include a fixing unit for fixing an image, and the predetermined activation step is a heating step from when the heating of the fixing unit is started until the operation of the image forming apparatus becomes possible.
[0012]
Alternatively, the above-described component includes a fixing unit for fixing an image, and the predetermined activation step includes a first heating step from when heating of the fixing unit is started to when driving of the fixing unit is started, and a driving step. Is a second heating step from the start of the operation to the time when the apparatus can be operated.
[0013]
The non-volatile memory is made up of an EEPROM (Electrically Erasable Programmable ROM).
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 shows an example of an image forming apparatus to which the present invention is applied. The image forming apparatus 1 includes a display unit 2, an operation input unit 3, a document reading unit 4 including a CCD, a printing unit 8, and a control unit 9 for controlling all of them. I have. The printing unit 8 further includes a paper feeding unit 5 including a first paper feeding unit 5a and a second paper feeding unit 5b that store and feed the paper P, and forms an image on a photoconductor and transfers the image to the paper P. An image forming unit 6, a registration roller 16 for temporarily stopping and bending the sheet P fed from the sheet feeding unit 5 to measure a timing of conveying the sheet P to the image forming unit 6, and a fixing unit for fixing an image to the sheet P. 7 is roughly constituted.
[0015]
The image forming unit 6 also rotates the photoconductor 10 in a clockwise direction in the figure, a charging unit 11 that charges the surface of the photoconductor 10, and exposes the charged photoconductor 10 to form an electrostatic latent image. An exposure unit 12, a developing unit 13 that develops the electrostatic latent image as a visible image with toner via a developing roller 13a, a transfer unit 14 that transfers the visible image of the toner onto the paper P, And a cleaning unit 15 that removes residual toner not transferred to the photosensitive member 10 from the surface of the photoconductor 10.
[0016]
Further, the fixing unit 7 includes a fixing roller 18 that is heated to a fixing temperature by a heater 17 and fixes the visible image of the toner with the heat, and a thermistor 19 that detects the temperature of the fixing roller 18. .
[0017]
The above configuration will be specifically described with reference to a block diagram. FIG. 2 is a block diagram showing a main part of the image forming apparatus 1 according to the present invention. The control unit 9 uses a CPU 20, a program ROM 21 composed of a flash memory for storing a control program for the image forming apparatus 1, a work RAM 22, which is a work storage device, and an EEPROM. And a data ROM 23 for backing up and storing the fluctuation data.
[0018]
Further, the display unit 2, the operation input unit 3, the document reading unit 4, the sheet feeding unit 5, the image forming unit 6, and the fixing unit 7 described with reference to FIG. Connected. Other electric components include a drive unit 24 including a plurality of motors and clutches (not shown), a temperature sensor such as a thermistor 19 (FIG. 1), and a position sensor (not shown) for detecting the position of each motor. ) And a sensor input unit 25 for inputting a sensor from a rotation speed sensor (not shown) for detecting the rotation speed and the like is connected to the control unit 9. When a facsimile transmission / reception function or a printer function for receiving and printing print data from an information processing apparatus is required, a facsimile controller 26 and a printer controller 27 are connected to the control unit 9 respectively.
[0019]
A case in which the image forming apparatus 1 is activated in the above-described configuration as in the related art will be described with reference to FIGS. FIG. 3 is a schematic flowchart in a case where the image forming apparatus 1 is activated in a conventional sequence. When the power is turned on, the control parameters and variation data stored in the data ROM 23 are read into the working RAM 22 in S1. When the reading of all data is completed, in S2, for example, display such as Wait display is performed based on the display control parameters for controlling the display unit 2 and the language data. Almost simultaneously, in S3, the heater 17 of the fixing unit 7 is turned on. In S4, the temperature at which the thermistor 19 rises is detected based on the fixing control data already read from the ROM 23, and when the fixing unit 7 reaches the preparation temperature, the fixing unit 7 and the image forming unit 6 are driven in S5. A main motor (not shown) of the driving unit 24 is operated. When the main motor is driven, the temperature in the apparatus and the temperature of the fixing unit 7 become uniform, and the temperature further rises. In S6, when the thermistor 19 detects a predetermined fixing temperature further based on the fixing control data, the fixing operation of the fixing unit 7 is enabled. In S7, the display of the display unit 2 is changed based on the display control parameters. Then, an operation relating to printing is received from the operation input unit 3, and the control unit 9 prepares for various controls for printing.
[0020]
Actually, when the data ROM 23 is an EEPROM, it only takes about one minute to read the fixed data and the variable data such as the control parameters stored in the data ROM 23 into the working RAM 22 in S1. Can not. If the same operation is performed using a flash memory, the operation is completed in a few seconds. Therefore, compared to the case where a flash memory is used, the device requires an extra startup time of about one minute.
[0021]
In the image forming apparatus 1, the fixing unit 7 is used to fix the visible image formed by the toner with heat, and the fixing roller 18 provided in the fixing unit 7 is heated to a predetermined fixing temperature by the heater 17, and the heat is applied to the toner. Fix the visual image. Actually, when the image forming apparatus 1 is started and the temperature of the fixing roller 18 reaches a preparation temperature slightly lower than the fixing temperature, the fixing roller is rotated by a motor (not shown) in order to make the surface temperature of the fixing roller 18 uniform. Let it. Thereafter, when the temperature of the fixing roller 18 reaches the fixing temperature, an image forming operation can be performed. Therefore, it takes several tens seconds to several minutes until the fixing roller 18 reaches the preparation temperature from the start of the normal image forming apparatus 1 and several seconds to several tens seconds until the fixing roller 18 reaches the fixing temperature from the preparation temperature. , See FIG. 1). This period is a period that is always necessary for the activation of the image forming apparatus, and in any case, the image forming operation cannot be performed. Therefore, by reading the control parameters necessary for the subsequent operation of the image forming apparatus 1 from the data ROM 23 during that period, it is possible to avoid providing an extra start-up time for reading the control parameters. This is the basic idea of the invention.
[0022]
Based on such a concept, a flow at the time of starting the image forming apparatus 1 according to the present invention will be described with reference to FIG. FIG. 4 is a schematic flowchart for explaining a sequence at the time of starting the image forming apparatus 1 according to the present invention.
[0023]
When the power is turned on, in step S11, among the control parameters stored in the data ROM 23 (EEPROM), display control parameters for controlling the display unit 2, language data, and the like necessary for display on the display unit 2 are displayed. Only the data is read into the working RAM 22. Since the data size is small, the reading is completed in a short time. Thereafter, in S12, display such as Wait display is performed on the display unit 2 based on the read display control parameters and the language data. When the reading of the control parameters for display is completed, the control parameters for the fixing of the fixing section 7 are read from the data ROM 23 to the working RAM 22 in S13 almost simultaneously with or slightly after S12. Since the data size of the fixing control parameter of the fixing unit 7 is also small, the reading is completed in a short time.
[0024]
Next, in S14, the heater 17 of the fixing unit 7 is turned on. Thereafter, based on the fixing control parameters read in S13, the thermistor 19 starts detecting the rising temperature of the fixing unit 7. Since it takes several tens of seconds at the earliest for the fixing unit 7 to reach the preparatory temperature, the time during this period is used, and in S15, the main motor of the driving unit 24 for driving the fixing unit 7 and the image forming unit 6 is used. The drive control parameters necessary for the next operation such as the rotation speed and the developing bias and the control after the start-up is completed are read from the data ROM 23 to the work RAM 22. Since the drive control parameters are also small in size, the reading is completed in a short time.
[0025]
In S16, when the thermistor 19 detects that the temperature of the fixing unit 7 has reached the preparatory temperature, in S17, the driving of the main motor is started based on the driving control parameters for which reading has already been completed. It takes several seconds to several tens of seconds for the temperature of the fixing unit 7 to rise from the preparatory temperature to the predetermined fixing temperature. During that time, in S18, together with other control data such as the amount of deflection of the resist for timing the paper P, The variation data such as the number of copies and the history are read from the data ROM 23 into the work RAM 22. Since the other control data and the fluctuation data have small capacities, the reading is completed in a short time. Then, in S19, when the thermistor 19 detects a predetermined fixing temperature based on the fixing control parameters already read in S13, the fixing operation of the fixing unit 7 becomes possible. Thereafter, in S20, the display of the display unit 2 is changed based on the above-described display control parameters, an operation relating to printing is received from the operation input unit 3, and the control unit 9 prepares for various controls for printing. Thereafter, image formation can be performed.
[0026]
As described above, according to the present invention, the control parameters and the fluctuation data that require a long time to read from the data ROM 23 are not read continuously until the reading is completed, but are read in units required for controlling the subsequent operations. The startup time is shortened by sequentially reading the image data during at least a predetermined period required for starting the image forming apparatus 1.
[0027]
In the present embodiment, the data ROM 23 composed of an EEPROM has been described as an example of a nonvolatile memory. However, the present invention is not limited to this example. The present invention can be practiced even when used.
[0028]
【The invention's effect】
As apparent from the above description, according to the present invention, it is possible to store control parameters and variation data in a nonvolatile memory in advance if a long time is required to read the data from an EEPROM or the like. As a result, the cost of the apparatus can be reduced.
[0029]
Further, at the time of starting the apparatus, these control parameters and fluctuation data are divided into units necessary for controlling the subsequent operations, and are sequentially read at least during a predetermined period required for starting the image forming apparatus. , It is possible to reduce the start-up time.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating an example of an image forming apparatus to which the present invention is applied.
FIG. 2 is a block diagram showing a main part of the image forming apparatus 1 according to the present invention.
FIG. 3 is a schematic flowchart when the image forming apparatus 1 is activated in a conventional sequence.
FIG. 4 is a schematic flowchart for explaining a sequence at the time of starting the image forming apparatus 1 according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Display part 3 Operation input part 4 Document reading part 5 Paper supply part 5a Paper supply unit 5b Paper supply unit 6 Image formation part 7 Fixing part 8 Printing part 9 Control part 10 Photoconductor 11 Charging part 12 Exposure part 13 Developing unit 13a Developing roller 14 Transfer unit 15 Cleaning unit 16 Registration roller 17 Heater 18 Fixing roller 19 Thermistor 20 CPU
21 Program ROM
22 Working RAM
23 Data ROM
24 Drive unit 25 Sensor input unit 26 FAX controller 27 Printer controller P Paper

Claims (4)

In an image forming apparatus that stores control parameters for controlling components in a non-volatile memory and executes a series of a plurality of startup steps to start up the apparatus,
An image forming apparatus characterized in that, during execution of a predetermined startup step, control parameters necessary for the next step and subsequent steps are read from the non-volatile memory. The component may include a fixing unit for fixing an image, and the predetermined activation step may be a heating step from when the heating of the fixing unit is started to when the image forming apparatus can be operated. The image forming apparatus according to claim 1, wherein: The component includes a fixing unit for fixing an image, and the predetermined activation step is a first heating step from the start of heating of the fixing unit to the start of driving of the fixing unit; 2. The image forming apparatus according to claim 1, wherein the second heating step is a period from when the driving is started to when the image forming apparatus can be operated. 3. The image forming apparatus according to claim 1, wherein the nonvolatile memory includes an electrically erasable programmable ROM (EEPROM).

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